Genetic linkage maps of Dendrobium moniliforme and D. officinale based on EST-SSR, SRAP, ISSR and RAPD markers

The genome organization of Dendrobium species remains largely unexplored. An F1 family derived from the controlled interspecific hybridization between Dendrobium moniliforme and D. officinale were used to create genetic linkage maps of parental Dendrobiums using double pseudo-testcross strategy. A total of 422 markers, including 66 EST-SSR, 126 SRAP, 74 ISSR, and 156 RAPD markers, showed expected Mendelian segregation ratio and were used for genetic map construction. Genetic linkage groups with Kosambi genetic distances were constructed using a LOD score ≥ 4 and a recombination threshold of 0.4. The map of D. moniliforme was 1127.9 cM in total length with 165 marker loci distributed in 17 linkage groups; and the D. officinale map consisted of 19 genetic linkage groups with a total length of 1210.9 cM positioned by 169 marker loci. The genetic maps constructed in this study can serve as a reference linkage map of Dendrobium species for efficient studies of comparative genetics, genetic mapping of traits with economic interest, and marker-assisted selection in horticultural breeding.

► An F1 family derived from the controlled interspecific hybridization between Dendrobium moniliforme and D. officinale were used to create genetic linkage maps of parental Dendrobiums using double pseudo-testcross strategy. ► A total of 422 markers, including 66 EST-SSR, 126 SRAP, 74 ISSR, and 156 RAPD markers, were used for genetic map construction. ► The map of D. moniliforme was 1127.9 cM in length with 165 marker loci distributed in 17 linkage groups; and the D. officinale map consisted of 19 genetic linkage groups with a total length of 1210.9 cM positioned by 169 marker loci. ► The genetic maps can serve as a reference linkage map of Dendrobium species for efficient studies of comparative genetics, genetic mapping of traits with economic interest, and marker-assisted selection in horticultural breeding.